Urticaria: selected highlights and recent advances

Utility of routine laboratory testing in management of chronic urticaria/angioedema

BACKGROUND

Laboratory tests are routinely ordered to identify or rule out a cause in patients with chronic urticaria/angioedema (CUA). The results of these tests are usually within normal limits or unremarkable.

OBJECTIVE

To investigate the proportion of abnormal test results in patients with CUA leading to a change in management and in outcomes of care.

METHODS

Retrospective analysis of a random sample of adult patients with CUA from 2001-2009.

RESULTS

Cases totaled 356: 166 with urticaria and angioedema (AE), 187 with urticaria, and 3 with only AE. Patients were predominately women (69.1%) and white (75.6%), with a mean age of 48 ± 15 years. Abnormalities were commonly seen in complete blood counts (34%) and in complete metabolic panels (9.4%). Among the 1,872 tests that were ordered, results of 319 (17%) were abnormal. Of 356 patients, 30 underwent further testing because of abnormalities in laboratory work. This represented 30 of 1,872 tests (1.60%). Only 1 patient benefited from a subsequent change in management.

CONCLUSIONS

Laboratory testing in CUA patients referred for an Allergy and Immunology evaluation rarely lead to changes in management resulting in improved outcomes of care.

Anti-immunoglobulin e in the treatment of refractory atopic dermatitis

Atopic dermatitis (AD) is a common diagnosis seen in both children and adults, and it is often the first manifestation of atopic disease. Research has shown a strong correlation between serum IgE levels, the severity of atopic dermatitis, and co-existing asthma and/or allergic rhinitis. Omalizumab (Xolair, East Hanover, NJ; Genentech, South San Francisco, CA) is a monoclonal antibody to human IgE and is currently Food and Drug Administration (FDA) approved for the treatment of asthma. We present 3 patients with severe, treatment resistant atopic dermatitis whose cutaneous symptoms significantly improved by treatment with omalizumab.

Chronic urticaria: the autoimmune paradigm

Chronic urticaria is a disease consisting of spontaneous pruritic welts, present on all or most days for more than 6 weeks. It is commonly supposed to be allergic in origin, although allergy is not the cause in the majority of cases, and it has therefore been termed 'chronic idiopathic urticaria'. Recent evidence indicates that at least a subset of patients in whom no extrinsic or internal cause can be identified are in fact autoimmune in origin. This is based mainly on the detection of pathogenic autoantibodies to the high-affinity immunoglobulin E receptor FcepsilonR1, which are thought to activate cutaneous mast cells. In this article, we review the evidence that has given rise to this autoimmune 'paradigm' and its impact on diagnosis and management.

Allergic skin disease: major highlights and recent advances

AD, urticaria, and ACD account for a large percentage of the skin disorders that present at medical offices and emergency departments. With a high degree of morbidity, these diseases can be extremely difficult to manage. Consequently, these diseases continue to be the focus of much of the new research in the field. Recent studies have furthered the understanding of the complex relationship between immune and nonimmune factors in the pathogenesis of these disorders. This research has quickly led to the development of new treatment modalities and protocols for patient care, especially for AD. However, further discovery will be necessary to optimize the management of these often-vexing conditions.

Urticaria

Urticaria with or without angioedema is frequently encountered in primary care medicine. Although many patients and physicians think that urticaria is evidence of an IgE-mediated allergic reaction, often the etiology of urticaria is unknown. This uncertainty frequently results in patients enduring unnecessary lifestyle changes or extensive testing. In more persistent cases, patients achieve control of their disease only with the use of more toxic medications, such as corticosteroids, and this can lead to a range of systemic complications. Acute urticaria is typically due to a hypersensitivity reaction while chronic urticaria has a more complex pathogenesis. Antihistamines remain the mainstay of symptomatic treatment for both.